Circular knitting machine



Nov. 12, 1957 Filed March 51, 1953 4 Sheets-Sheet 1 Invenlors Mat {1 9M 2 ttorney Nov. 12, 1957 F. E. DEANS ET AL 2,812,649

CIRCULAR KNITTING MACHINE Filed March 31, 1953 4 Sheets-Sheet 2 Inventors W 5'. $1M B WW ttorne y Nov. 12, 1 957 F. E. DEANS ET AL 2,812,649

CIRCULAR KNITTING MACHINE 4 Sheets-Sheet 3 Filed March 51, 1955 Nov. 12, 1957 F. E. DEANS ET AL 2,812,649

CIRCULAR KNITTING MACHINE Filed March 31, 1953 4 Sheets-Sheet 4 I nventora ttorney United States Patent Otlice 2,812,649 CIRCULAR KNITTING MACHINE Frederick Edward Deans and Carlyle Herbert Wainwright, Leicester, England, assignors, by mesne assignments, to The Bentley Engineering Company Limited, Leicester, England Application March31, 1953, Serial No. 345,792 Claims priority, application Great Britain April 7, 1952 7 Claims. (Cl. 66--14) This invention concerns circular knitting machines of the type (hereinafter referred at the type specified) having a rotatable and oscillatable needle cylinder, inside sinkers (i. e. sinkers mounted and controlled inside the needle circle). mounted in a sinker ring inside the needle cylinder, and sinker operating cams inside the sinker ring. The invention is primarily concerned with machines of this type having two opposed needle cylinders equipped with double ended needles capable of transfer from one cylinder to the other by means of sliders for the purpose of changing over from the production of rib fabric to plain fabric and for the purpose of altering the character of the rib fabric. In general such machines have cylinders disposed one above the other to rotate and oscillate about a common vertical axis, and those machineswhich are sold under the registered trade mark Komet are an example to which this invention is applicable.

In superimposed needle cylinder machines of the type specified the sinkers are usually carried in a grooved ring so as to be capable of projection between the needles to the outside of the needle circle to engage the yarn and of retraction to draw the yarn inwardly so as to assist in the loop formation and so as to hold down the loops as the needles rise. The cams necessary to give the sinkers their movement are usually mounted on a sleeve which extends downwards through the bottom needle cylinder and rests on a fixed part of the machine below the needle cylinder and the cylinder-driving mechanism, and the sinker ring is rotatably supported around the sinker cams.

Mechanism is usually provided ona fixed part for adjusting the sleeve vertically so that the height of the sinkers may be set to a nicety. The fixed part also usually carries stop mechanisms for locating the sleeve circumferentially in relation to the needle cylinder and for adjusting the timing of the sinker movements in relation tothe needle movements. This mechanism usually incorporates two opposed stops between which a suitable part on the sleeve is disposed so that during rotation of the needle cylinder the sleeve due to frictional drag applied by the cylinder is positioned by one stop, and as the needle cylinder reverses its direction of movement during reciprocating" knitting the sleeve is moved over from one stop to the other due to drag in the reverse direction. The sinker cams are keyed to the sleeve and the sinker ring is keyed to the needle cylinder so that the sinkers are carried around the stationary sinker cams Usually two plain journal bearings are provided between the retatable and oscillatable needle cylinder and the relatively stationary sleeve, one just below the sinker ring and one near the lower end of the needle cylinder. These serve to hold the sleeve concentrically with the needle cylinder and for many years have been a source of trouble in knitting machines of the type under discussion because they are difficult to lubricate. In particular the lower bearing is liable to become dry and in some cases rusty and if this happens seizure occurs.

A number of proposals have been made for overcoming Patented Nov. 12, 1957 this difiiculty and some of them have been concerned with manual or automatic lubricating devices for the bearings. Because of the extreme inaccessibility of the bearings such lubrication systems have not achieved practical success. Other proposals have involved the use of. a11ti-friction bearings such as ball or roller bearings, requiring no lubrication over a long period. A disadvantage of such proposals is that owing to the very restricted space available to accommodate a bearing of this kind the section of the bearing is necessarily very small in relation to its diameter so that the bearings have had to be specially made and are extremely fragile. i

The present invention seeks to overcome diiliculties discussed above and it provides a circular knitting machine of the type specified, characterised by the combination of a sleeve, supported and centralised by the sinker cams or a part to which they are connected, having a bearing in the sinker ring or in a member in the immediate vicinity of the sinker ring (e. g. a member connected directly to the sinker ring) which sleeve extends within the cylinder from the cams to beyond the end of the cylinder remote from the sinker ring, centralising means beyond said end of the cylinder for centralising the sleeve in a stationary part of the machine, and stop mechanism. beyond said end of the cylinder for controlling the angular relationship of the sleeve and the sinker cams to the cylinder and for permitting and determining limited rotational movement of the sleeve and cams in relation to the cylinder as the latter reverses. It will therefore be seen that there is only one bearing viz. that between the cams or a part to which they are connected and the sinker ring or a member in the immediate vicinity of the sinker ring. This bearing, being disposed in the vicinity of the open end of the needle cylinder, can readily be lubricated. The centralising means does not serve as a bearing in the normally accepted sense of that word, for relative movement b tween the sleeve and this centralising means only takes place at the time that the needle cylinder reverses its swing during reciprocating knitting.

The foregoing and other features of the invention are incorporated in the construction which will now be described by way of example with reference to the ac companying drawings in which Figure l is a sectional elevation through the relevant parts of a knitting machince according to the invention;

Figure 2 is the elevation thereof looking from the left of Fig. 1;

Figure 3 is an underneath view of the needle cylinder and associated parts;

Figure 4 is a perspective view of one anism, and

Figure 5 is a view corresponding to Fig. 1 but illusa bevel gear 7. f lnside the t'opend of the needle cylinder;

1 there is a sinker ring 8 which is keyed to it at 5 for up and down adjustment and has its inner periphery of part-circular sectional form. This sinker ring 8 is cut with part-circular tracks 10 in which curved inside sinkers 11 of known form slide, and the sinkers are operated by cams in a cam ring 12, the said cams providing a. track 13 for the sinker butts 14.

The cams 12 are attached to a throat ring 29 and have a bearing on the internal periphery of the sinker ring 8, their exterior periphery being of part-circular sectional part of the mech-- 3 form to match the shape of the sinker ring. They are prevented from rotating with the needle cylinder 1 by the following mechanism. Secured to the cam ring 12 there is a sleeve which extends down inside the needle cylin der 1 and is spaced interiorily from it. The lower end of this sleeve 15 protrudes through a suitable aperture in a stationary member 16 attached to the part 5 so that the sleeve is centralised, and this member 16 carries lugs 17, 18, see also Figs. 2 and 3, provided with opposed adjustable stop screws 19, 211, between which a parallel sided tongue 21 on the sleeve is disposed. The tongue 21 is provided by forming a recess each side of it in the lower end portion of the sleeve 15. It will therefore be appreciated that during rotation of the needle cylinder 1, the tongue 21 is positioned by one of the stop screws 19, so that the angular relationship of the sleeve 15 and the sinker earns 12 to the needle cylinder 1 is determined. This relationship determines the timing of the sinker movements in relation to the needle movements and it may be adjusted by adjusting the stop screws just mentioned. During reciprocatory knitting the needle cylinder oscillates to and fro. At each reversal of motion of the needle cylinder, the drag between the sinker ring 3 and the sinker cams 12 and also the drag exercised on these cams by the sinker butts 14, tends to cause the sleeve 15 to move with the cylinder. The slight drag between the stationary centralising part 16 and the base of the sleeve 15 does not prevent this movement of the sleeve 15, which movement is terminated by one of the stop screws 19, 26. Thus throughout reciprocating knitting the tongue 21 moves to and fro or shogs between the screws 19, 2G.

The sleeve 15 may be suspended from the sinker cam 12 in any suitable manner. In the illustrated construction an internal flange 22 at its upper end is locked between said cams and an inner clamping sleeve 23 which is screwed on to the lower end of the throat ring 29. This inner sleeve 23 is itself locked against unscrewing by grub screws 24, shown in Fig. 3, screwed into the sleeve 15 and adapted to be tightened against the inner sleeve 23. The latter extends below the sleeve 15 and is formed with pairs of diametrically aligned holes 32 for the reception of a tommy bar to facilitate screwing and unscrewing the inner sleeve.

The sinker ring 8 together with the sinkers 11, sinker cams 12 and sleeves 15 and 23 is adjustable up and down the needle cylinder 1 in order to regulate the height of the sinkers in relation to the top end of the needle cylinder. For this purpose the sinker ring 8 is supported on the top end of a sleeve 25 slidably mounted in the needle cylinder 1 and driven to rotate with it by means of tongue 26 (Figs. 1 and 4) which fits like a key in a slot 27 in the needle cylinder. This tongue 26 rests on an adjustment screw 28 which extends up through the cylinder base 2 and is provided with a lock nut 31.

Fig. 5 illustrates an alternative construction wherein the sleeve 25 has no offset tongue such as 26 and is mounted to rotate with the needle cylinder simply by means of the friction between it and the cylinder sup plemented by that between it and a headed locating screw 28. It will be noted that the latter supports the weight of the sleeve 25, sinker ring 8, throat ring 29 and parts carried thereby. The screw 23 extends through and engages with a screw threaded aperture in a part of the cylinder base 2 and its enlarged head engages the lower edge of the sleeve 25. Thus by turning the screw 28 the 4 heightwise adjustment of the sinkers 11 relatively to the needle cylinder 1 may be varied. A lock nut 31 is provided to retain the screw 28 in adjusted position. To provide clearance between the head of the screw 28 and the needle cylinder the adjacent portion of the latter is slotted as indicated at 30.

What we claim is:

1. In a circular knitting machine of the type specified the combination comprising a support, a needle cylinder rotatably mounted on said support, a sinker ring carried in one end of the cylinder, to rotate therewith, means for supporting and positioning said sinker ring in the end of the cylinder, sinker cams disposed within the sinker ring and supported heightwise thereby, a centralising sleeve, means mounting said sleeve in fixed and concentric relationship with the sinker cams, said centralising sleeve extending within said cylinder from the sinker cams to beyond the opposite end of the cylinder with clearance between said sleeve and the interior of the cylinder, centralising means fixed in relation to said support and positioned beyond said opposite end of the cylinder for centralising said sleeve and stop mechanism to co-operate with said sleeve beyond said end of the cylinder for controlling the angular relationship of the sleeve and sinker cams to the cylinder and for permitting and determining limited rotational movement of the sleeve and cams along with the cylinder when the direction of rotation of the cylinder reverses.

2. The combination according to claim 1 comprising a throat ring on which the sinker cams are carried and having the said centralising sleeve attached to the throat ring and the said centralising means constituted by an apertured member in the aperture of which the said sleeve is centralised.

3. The combination according to claim 2 comprising an inner clamping sleeve extending through said centralising sleeve for securing it to thethroat ring.

4. The combination according to claim 3 comprising inter-engaging screw threads on the clamping sleeve and throat ring and an internal flange on the centralising sleeve whereby the latter is clamped by the clamping sleeve to the throat ring.

5. The combination according to claim 1 comprising a supporting sleeve carrying the sinker ring and serving to centralise the latter by engagement with the cylinder, and adjusting means for varying the position of said supporting sleeve lengthwise of the cylinder to vary the setting of the sinker ring and sinker cams in relation to the cylinder.

6. The combination according to claim 5 comprising means mounting said adjusting means to rotate with the needle cylinder.

7. The combination according to claim 5 having said adjusting means constituted by an adjustable screw abutment to engage that end of the supporting sleeve which is remote from the sinker ring.

References Cited in the file of this patent UNITED STATES PATENTS 1,198,280 Rush Sept. 12, 1916 1,716,691 Grieve June 11, 1929 2,736,177 Bristow Feb. 28, 1956 FOREIGN PATENTS 429,056 Great Britain May 23, 1935 

